Musings on flood control
I attended the city of San Marcos flood mitigation meeting last night at the activity center. I can’t help but wonder if the real purpose of this project is not to save the Blanco Gardens subdivision, but to remove a lot of land on the east side of San Marcos from the 100-year floodplain and allow it to be developed.
The slide that really told the story is the one that showed the present 100-year floodplain and the new improved floodplain that was considerably smaller.
Engineers have a terrible habit of trying to move floods around. But we have to realize that a flood like the one that occurred in May of 2015 has a mind of its own. It doesn’t like to be moved around. It is heading to the coast and it really doesn’t care where our flood maps want it to go. It chooses new paths. It may parallel the river at times, but it has no concern about staying where the engineers say it should stay.
And, the engineers don’t tell you that awful truth. The bottom line is that they are not trying to control the 1,000 year flood. Because FEMA really just cares about the 100-year floods (and maybe they mention the 500-year floods). But if you have a flood that really overwhelms the system like the May 2015 flood — well, we can’t plan for everything.
If you ask the engineers what will happen, once all their berms and ditches are complete, if we have another flood like the one in May of 2015. The bottom line is that pretty much the whole area that flooded in 2015 will flood again.
So, what is the answer? Well, rather than trying to move the flood out of the way of our houses, we need to move our houses out of the way of our floods. Some homes simply need to be removed or rebuilt. But a lot of homes can be raised. These are the homes that are on piers and beams. You raise them up (a couple of feet above the May 2015 flood). The city could partner with some firm that raises homes and maybe hire crews and concrete pumping trucks. If a whole subdivision has to be raised, the price per home might be greatly reduced. The price of the ditches and berms will be approximately $70,000 per home. We can raise a heck of a lot of homes for that much money. Actually the cost of raising a home may be half of that amount, which will leave a lot of money for buying the homes that can’t be raised (homes on slabs). It may be easier to make some of the homes “flood proof.” Fiberglass insulation and stud and sheetrock walls can be replaced with foam cement that both insulates and is waterproof. Ceramic tiles on the floors. Cabinets and furniture that can get wet. It is not as good as raising a home, but if the home can’t be raised, and if the owner simply doesn’t want to move, then it might be an option that that owner can accept.
There is another option that might be considered. The city has 25 million dollars to save Blanco Gardens. For that amount of money, they should be able to buy the Woods Apartments, tear them down, and return the property to its original state. There is no guarantee that such an action would save all the houses in Blanco Gardens, but it sure might do as well or better than the current options that are on the table.